Utterly Confused About Periodic Trends

Trends for the elements may be either horizontal or vertical. The combination of these leads to diagonal relationships that increase either from the lower left to the upper right on the periodic table or from the upper right to the lower left. There are few trends that increase along another diagonal or that are only horizontal or vertical. You should remember that the noble gases are not included in some trends. In addition, hydrogen is often an exception to many trends. 

There are other exceptions. For example, the EA of fluorine is lower than expected. This is because of the repulsion of the electrons in the small fluoride ion. If the ion were larger, the repulsion would be lower. The larger chlorine atom has the highest EA of all the elements. 

What term refers to a column on the periodic table  

True/False. The ionization energy may be either endothermic or exothermic. 

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